1. Field of the Invention:
This invention relates in general to fire escape devices, and in particular to a drum and cable unit for lowering an individual from a damaged structure.
2. Description of the Prior Art:
Many deaths result each year from building fires in which people are trapped in floors too high to be reached by fire truck ladders. There have been many proposals in the patented art to provide fire escape devices. One common proposal is a small portable drum and cable kept in higher floors for emergency use. Should fire occur, the user breaks a window, secures the free end of the cable to a building part, then lowers himself to the ground or to a safe level.
One deficiency with some of the proposals, such as shown in U.S. Pat. No. 859,266 issued to Ulery and U.S. Pat. No. 2,409,767, issued to Larson, is that the user has to adjust a friction type brake to control the speed of descent. Should the user panic or be unconscious, an accident may occur. Other proposals disclose automatic governors for speed, such as shown in U.S. Pat. No. 2,500,884 issued to Tessin and U.S. Pat. No. 4,063,615 issued to Knepp. Tessin utilizes a fluid restricting device that requires reverse winding of the cable and the drum at periodic points. Knepp utilizes a centrifugal friction type governor in which additional speed control appears to be required through manual operation of a conventional brake band.
Also, none of these devices shown appear to have means provided to absorb shock due to jerking of the line. If the user jumps, as is likely, the jerk might part the line or damage the speed governor. In U.S. Pat. No. 939,375 issued to Andrews, a coil spring is disclosed that winds more tightly as the user descends so that the unit can return to the upper level once the user reaches ground and releases it. Possibly the spring will also absorb some shock, however, the speed control is manual.
In addition, none of the patents disclose a compact package for storage. Rather the straps for supporting the body are hanging loose from the carriage, making it easy for them to tangle, and also more bulky to store.